Truck dock bumper



I III/111111 F. B. SCHUYLER TRUCK DOCK BUMPER Feb. 12, 1957 INVENTOR. FEED 5. 30w )4 52 A 7' Toe/v5 Y5 United States Patent Ofifice Re. 24,276 Reissued Feb. 12, 1957 cation; matter printed in italics indicates the additionsmade by reissue;

This invention relates to protective resilient bumpers for truck loading docks and other structures subject I to damaging impacts of large vehicles or other heavy mobile equipment. A general object of the invention is an improved, shock-absorbing dock bumper of simple,.inexpensive, rugged and dUIEbIQCOBSiI'UCfiOIl, adapted for mounting on a dock wall, either singly or in groups to covera selected impact zone.

Experience has revealed that the usual wood or steel protectiveguards employed in truck loading docks are more expensive than they might seem to be because'of' the necessity'forrather frequent replacements due to impact damage. Moreover,such guards do not tend tosoften the impacts-of the vehicle with the dock, hence are of little aid in preventing damage of truck parts or breakage-of fragile items of freight. Ithas been evident, therefore; that a relatively inexpensive, conveniently mounted resilient dock bumper, having the necessary'ruggedness and wearing qualities, is desirable;

The resilient body portion of'theimproveddock'bumper comprisesa plurality of rubberor rubber-like" strips:" such assections cut from discarded automobile the gas-- ings,-.forexample, arranged face to face in-a-stack and held" together by bumper mounting structure. Suchstructure comprises a pair ofstructural angle brackets havingflanges constituting. bearing plates, betweenflwhich the stack of strips isheld, and complemental fiangesconstituting. mounting. plates projecting: endwisefrom-"the stack-for bolting of the bumper toadock wall with the individual strips at right'angles to'the wall. A pair "of through-bolts extends through aligned apertures in---the stacked strips and interconnects the bearingplate flanges of the'brackets to'form a rigid mounting structure:

For protection of long walls anumber of these-bumpers" may be mounted in series relationship along an impact zone. Wherea group of bumper units ar'e'rnou'nted in that manner, it is'conv'enient to overlap the mounting flanges at adjoining ends'of adjacent bumper units so that such flanges may be secured to the wall by the same anchor belts and sotha't a minimum unprotected gap will be -le'ft between successive units". I,

Whenthe'resilient strips making up" the somet me bumper are sections cut from discarded automobile tire casings or"sirni1a'r curved stock, thereisia tendricy'foi the" strips to retain their 'curvaturewhen mounted in the bumper unit between the strucfural angle brackets. If

this tendency were not overcome tow a considerabledegi'e'ftl'ie' stiips wearers-1n 'tdbiickle'niore "readily than is desired when subjected to edge impacts. A further feature of the invention, therefore, comprises a bumper unit of the type described, in which the end strips are arranged so that their direction of curl is toward the adjoining strips in the stack. Hence, such end strips will not curl appreciably over the adjoining bracket flanges, but will assume airiore orless' erect position most conducive to resisting impact loads in the planes of the strips.

Theseandother features, objects and advantages of the invention including certain details of its preferred form of construction will now become more fully evident from the following'deseription based upon the accompanying} drawings".

Figured is af'plan view showing part of'a group of' bumper unit'sm'ounted on a dock wall in horizontal se'ries relationship; v

Figure 2 is a front view'of an individual bumper unit havingpar'ts' broken away to showce'rtain details.

Figure 3 a corr'es'pondingendview of the bumper unit mounted on asupp'ortirig wall, with'parts broken awa Figure" A is'faf'fragmentary longitudinal sectidn taken on has in Figure 2; I V I Each bumpefunit'IO comprises a plurality of generallyrec tan'g iilar resilient-strips of rub'ber'or rubber-like' m'ar teriahsuch as the fabric-reinforced rubber in automobile tiie casi'rigsjfor example. Preferably the strips are cut froiri'thetre'ad portions of old" automobile and truck tire:

casings inorderto minimize the cost of' the bumper, the length of such strips extending circumferentially of the" ti'r'eI Such strips are arranged face-to-face in a stack, the length of which may'vary dependingupon design re uirementsorp'reference; In a typical case the bumper unit will betlire'e or four feet in length.

iTlista'ck ofjre's'ilientstrips l z constitutes the body of;

thebuinper. The strips are ap ertured to receive the two parallel thr'ou'gh i-ods 14, whichextend through the stackand interconnect corresponding flanges 16 of the strucanal angl'ei'mountin'g brackets 18, as shown. The bracket flanges" 16' functionas bearingplates abutting the end sti"ipsofthe stack over amajorportion of their area as shown in" Figures 2 and 3, which consequently support the strips against buckling when subjected to edge impacts. Asa further step. in minimizing the bucklingtendency' 0f thie strips under'inipact, care is taken that the end-most" strips inth'e stack, if they tend to curl inherently as theywillifcut from: old automobile tire casings, for'exmnple, curl'inward of the stack'or toward the adjoining-strips therein. a result the end strips do not curl'outwatdor over the bearingfianges of the brackets, but tend to re mainerect, or substantially so, with-relation to the wall W upon which the'bumper unit is mounted; This may be seen from Figure 4,in which all but 'the'endmosfstrip' in' the stack tend to curl to the right in-the-figurej whereas righthand strip is facing so that it'tends to curl toward the left; Obviously, other strips in-the stack,'such as thoseadjaeent to the strip 'at the extremerightofiFigure" 4, may be disposed to curl in the samedire'ction as 'it doles, except the strip; at the opposite end of'th e stack, which should curl towardthe= right.

will be noted in Figure 4' especially, andalso 'in" Figure 1, that 'the tie-rods 14*are*locatedat the sideoft-he" longitudinalcentral plane of the bumber remotefron'i Consequently, these rods; being its" impact surface. thus offset from the neutral axis,-will withstandtension produced by=tlie tendency of the bumper to" bend under an impact load; Thus thebumper willhave considerabw' stiflness against bending-deflection even'when'th bumper is' 'spacedoutward from the wall W, as sho'wnat thele'ft and ri'ght of Figure l.

The complemental flanges 20' of structural angl brackets 18 constitute mounting plates by which the bumper is mounted against the supporting wall W of the dock. These flanges are preferably coplanar with the back edges of the stacked strips, as shown in Figure 4, so that when the mounting plate flanges are secured to the wall W by bolts 22, such edges abut the wall surface. The middle bumper of the group appearing in Figure 1 is mounted on the wall W in that manner.

However, it is not essential in the improved bumper construction that the rear edges of the resilient strips actually contact the wall surface when the bumper unit is mounted on the wall. In fact, when a series of bumper units are mounted together, it is preferred that the flanges of adjoining ends of adjacent units overlap so that a single set of anchor bolts may be used to secure overlapping flanges to the Wall. In such case the bumper units are actually spaced outward an appreciable distance from the wall, namely the thickness. of one of the mounting flanges.

This is the case with respect to the bumper units Whose end portions appear at the right and left, respectively, in Figure 1. Because of the nature of the bumper unit mounting structure comprising the structural angle brackets and the through-rods which hold the resilient strips in a compact stack, the bumper acts as a shock resisting structural beam, in effect. It is capable of resisting heavy transverse impact loads applied intermediate the ends of the bumper, even though such ends be supported at outward spacing from the dock wall, as in the case of the end units appearing in Figure 1. In functioning as a structural beam of resilient properties, the strips themselves play an important part as a result of being clamped together between the structural angle mountings at the ends of the unit.

While the bumpers may be made in different sizes as previously mentioned, in a typical case a threeor fourfoot long bumper unit is made from rectangular strips about five inches by ten inches. The through-rods are of three-fourths inch diameter round steel, and the structural angle brackets are of standard three-inch angle-iron stock cut to the lentgh of the strips. The strips are, therefore, about two inches wider than the bracket flanges,

would have the objectionable feature of permitting rotation of the strips about-the rod axis.

In the illustrated case the through-rods have heads at one end and their opposite ends are welded or riveted to form heads while the rubber strips in the stock are held under suflicient clamping pressure between the structural angle brackets to render them substantially planar. Such pressure can be established by holding the assemblage in a press or vise until the ends of the through-rods are appropriately upset or welded on to the flanges 16 to maintain the desired pressure permanently. It will be evident, however, that these rods could take the form of throughbolts, if desired. In such case clamping pressure of the angle irons against the ends of the stack would be exerted by tightening the retaining nuts on the threaded ends of the bolts.

.Because the bumper units may be grouped closely together in series as in Figure 1, substantially complete shock protection along a wall of any length may be obtained. They may be secured in place by bolts, lug screws or equivalent means. This and other ways of using the improved bumper units will appear to those stack, respectively, and having their other flanges disposed substantially coplanar with one side of said stack and projecting oppositely endwise therefrom, said stack of strips having apertures therethrough disposed between the side of said strip stack substantially coplanar with such other angle flanges and the central plane of said stack parallel thereto and offset a substantial distance from such plane, and through-rod means extending through said bearing plate flanges and said stacked strips apertures, interconnecting said brackets to retain said strips clamped between the strip-engaging faces of the bearing platev flanges of such brackets,- such other flanges of such brackets constituting mounting plates for mounting the bumper by its ends.

2. Abumper for truck loading docks or the like comprising a plurality of resilent rubber-like strips arranged face-to-face in stacked relationship, a pair of structural angle brackets disposed at opposite ends of said strip stack, respectively, having bumper mounting flanges disposed in coplanar relationship and projecting away from said stack of strips with one face of each such flange exposed beyond the corresponding edge of said stack of strips, and each angle bracket having a strip stack clamping flange abutting the outer face of the adjacent end strip in such stack and contacting such strip face over a major portion of its area, said resilient strips and said angle bracket clamping flanges having aligned apertures therein, and through-rod means extending through such aligned apertures in said stacked strips and the clamping flanges of said angle brackets and interconnecting said clamping flanges .with said resilient strips clamped therebetween.

3. A bumper for truck loading docks or the like comprising a strip stack including a plurality of resilient,

rubber-like strips arranged face-to-face in stacked relationship and having aligned apertures therethrough extending transversely of said strips, a pair of stack-clamping and bumper-mounting angle abutment members having stack clamping flanges engaging opposite ends of said strip stack, respectively, and through-rod means extending through said aligned apertures of said strips and interconnecting said slack-clamping flanges of said angle abutment members with said strips clamped tightly therebetween as an integral unit, said angle abutment members'being disposed with their other, bumper-mounting flanges supportable on a wall to support the bumper, said 'l'lumper-mounting flanges being substantially coplanar with at least a substantial portion of the side of said strip stack adjacent 'to such wall.

References Cited in the file of this or the original patent UNITED STATES PATENTS.

patent France Jan. 12, 1914 

